Note: Descriptions are shown in the official language in which they were submitted.
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AN IMPROVED SOLAR ENERGY CONCENTRATING SYSTEM
~VING REPLACEABLE REFLECTORS
TECHNICAL l~lELD
s
The present invention relates to an ~nproved solar energy concGllhdli~ tGm
mco,~ldli,lg ~epldceable solar ener~y co.~ce~ ,n~cto.~. Prior s~vstems ~
required a structural~ stable ~olar enG~y concGllhdli.,g panel. The present m:vention
uses a col,-bL~hon of structurally stable b~r~ panels and i~exible solar e~G~y
0 conc.",hdh-4~ ,Gllcclu ~ to reduce ~ ty the ease and cost of le~lac.,~ refl~ctnr~
BACKGROUND ART
~ the past, solar energy Cf)~-C~ syste~s used sol~r energy collc~Lal;lg
reflectors that were ~hu~ dlly stable. However, wi~ ~ne, the reflector s~rf~cPs
suffercd a ~le~ tinn of reflectivity from attaclc by the we~ther. Prior systems
required the user to replace the entire reIlector. Typical~y, ~ese panels were heavy
and expensive.
DIS~I,OSIT~ O~ INVENTION
The present invention rel~tes to an improved solar ener~y concentrating system
2s incorporating replaceable solar energy concc11LIdl~g reflectors. Prior systerr~s typical~y
required a ~ dl~y stable solar energy concentrating panel. The present inventionu~se~s a comhin~hon of structural~y stable backing panels and flexible solar energy
conce~ dli-~g reflector~s to reduce .~ignifi-~ntiy the ease and cost of replacing arcuate
reflectors. (For the purposes of the present invention, arcuate ean refer to either
30 cylinArir~lly arcuate shapes, ~ntirl~tir~lly arcuate shapes or parabolically arcuate
xhapes.)
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In a single panel ~l~p~ ", a ma~ u~ ct~r, solar energy COl~C~ dLl~g
system c~ ~e foUowing e1 .. --t!', A reflector b~t ;--p panel has a concave and
arcuate conr~ n of up to 1~0 degrees, a lower edge, an upper edge, and c~ved
s lateral edges. (For the pu~ses of this inven~on, "lower" and "upper" do not e~press,
nf.c~ ;ly, a rela~ve po~ n b~,h.~ ~e edges, for; '~, if the reilector backing
panel has a 180 degree co..rg.~-~Lon, then these edges may be equidis~ant from the
s~po~ g surface for ~e l~lecl~ l.) The skyward surface of ~e len~l~l backing
panel is the concave s~ c~. The ~ l b~ft ;-~ panel is .l;-..~.nn:~ned and
0 col~ ed so as to pr~vide c~ r~ n~l stab~ity to an overlying solar energy
C~nf ~1~aLI~g re~lector. One of o,~ r sl~ll in the art can use vanous materials to
col~hu~,l a shu luld]]y stable reflector bac~ , paneL in~ in~ f~ir~ted metals oralloys, and molded l~ t.,s or co~,it,i..
A shu~ uypOll means extends benea~ the reilector backing paneL being
fi ...P .~ ned and col~,ui~d so as to ~U~J~)Oll at least the weight of the l~lle~,tur
backing paneL a solar energy cf~ ctf r, a solar energy co~f ~ dtil g refl~ct~ r, and a
solar energy coll~ctor ~7Uyp~/ll means. A typical example of a suitable means is a truss
such as a space truss, but others are known to those of ordir~y skill in the art. The
20 reflector ba~ panel is co~ cl~l to the ~ u~ lal support means so as to m~t~in the proper ~ ~.l .I;fm to the sly.
On top of the re~cctor b~c~ panel lies a flexible solar energy concc~lldlil~g
re~lector. (For the p~l3oses of t~is invention, "flexible" inr1lldes desc.;l,..~, a surface
25 or object that does not ~ ;.. a desired arcuate co,~uldlion to within severaldegrees of arc when unsupported.) The reflector has an upper edge, a lower edge, and
curved lateral edges. The reflector has a concave and arcuate co~,ulalion
complc~ to that of the relector ba~ g panel. Either the slyward surface is
highly reflective or the reflector is l.dlu,~alc;llt and the lower su~:face of the re~ector is
30 hi~ reflective with respect to inrf min~ radiant solar energy. The reflector can be
attached to the reflector backing panel by conventi~n~l f~ means. By not
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an a,.,~ly stable de~, one can ~ r~ntty lower the cost of r~ ,alillg
the l~ille~,tur. Also, by mal~n~ the solar reflector flexible, one ~ 1y reduces its
wei~ht, making it much easier to hal~o~l and physicaUy replace the reflector.
s A coL~.,tor ~upyOll mear~ is conn~cted ei~er to the reflector b~r.l~m~ panel,
~e ~I u.;lu~ polL means, or a ~ace und~lying the sl~ ual support means.
The conector support mean~ is di~posed above ~e re~lector so as to support a re:flected
soLar ener~y collc~ m a y1~d~ t .--i-.cd focal zone for c~ in~ the ~eilected solar
energy. In the case of a moveable collector system, such as one using cylin~1rirA~ly
0 arcuate reflectors, ~e collector ~upport means aLso ~lows the cnlk,ctt r to move
~uu~t~ ly within the pred~ t~ r~l focal zonc. The n~ture and size of a focal
collection zone depf-l-tlQ upon the shape of the ft~le~ and the shape of the co~e : :,r,
as is known to those of u~ uy sl~ll in ~e art.
lS ~ order to ga~er the rei lected solar ener~y, a solar ener~y coll-F ctor extends
e above and across the curved lateral edges of the 1ci~lc~,lul. The COJleCtl)liS.li",~ ;oned and co~ d ~o as to receive the reflected solar ener~y into a conduit
IhlU~ 1 which an ener~ a~ ftuid can flow, the ~luid being heated by the reflected
solar enF~.
O~er conventi~n~l elF ..~e..l~ include â means for po~itjon~ the co~ector in an
optimal position for co11~cting the reflFcted solar energy 11-1uu~l~uul a defined solar
cycle. (~ûr e~lnl l~, typically the solar cycle is ~e diurnal cycle.) The pociti ming
means is connected to ~hG collec~or support means. One of O1dil1al~y skill in the art can
25 ap~.e~iaLe that the positioning means can be of various embo~liment~ e. g., hydraulic,
mech~nic~1 or electrical.
Finally, a fluid transport system connects the conduit of the collector to a
the~nal energy use means or an energy storage means. The fluid transport mean~
30 circulates the sûlar-heated fluid through the conduit.
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l~he p~ent invention is pa.li~ul~ly suitable to ~ '- aTrays, or rows of
~c~In such an ~ a plurality of lcne~;lul~ and a ph~l~l;ty of
un~llyi~ .,nc~,lu~ bacl~ng panels are used, as desclibed above. If used in a row, the
curved lateral edges of each re~lector or each reflector backing panel are dimensioned
S and col~su.~d such that the curved 1ateral edge of a reflector or a reflector backing
panel can be placed ~dj~G~nt to the curved lateral edge of another leil~ r or ~nc~tl,
backing panel, so as to form a row of re~ector b ~t;~l~, panels with lei le~,lol~ on top.
~ The present improvement is also suitable for use in ~t~ n~rycf)ll~ct~r
10 applir-~l;nn~ Conven~ n~1 st~hon~-y cnll~ctor systems have a 1)~ ~ nil~g means and a
fluid l.~ls~ll system as ~es~rihed above. However, the collector support means is
~irnel,~ nPd and col~ ,d to hold the collector in a st~1ir~n~ry p~ i"n Mea-~wl.;lc,
the structu~l support means is ~ osed below or above the reflector so as to support
the re~lector in a ple~l~,t~ e~l focal zone for cQ11~ c1in~ the reilected sol~ ener~y
15 from the collector. With the present impro~,~n~elll, instead of rcq11irin~ the
rep1 ,e-..~ .1 of a moveable reflector, one uses a combination of the flexible reflector
and a rigid reflector b~ i~ panel.
20 BRIEF DESCRrPTION OF THE DRAWINGS
FIGURE 1 is a secti~n~l view of the present inven~on.
FIGURE 2 is an isometric view of the present invention.
2s
BEST MODES FOR CA~YING OUT THE L~VENTION
~ preferred embodiment of the present invention is shown in FIGURE l. The
30 illustrated embodiment is for a moveable collector system having a cylin~ric~lly arcuate
st~ti- n~-y reflector. A reflector ba~ panel (l0) 11nA~1i~s a solar ener~y
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cni.r.~..,l~"l;.~ reflector ~20). The re~lector b7~1~i~ panel has a s.~ ny ngid
concave and arcuate cl~-.r~ ..) of up to 18Q degree9. The reilector backing panel
has a lower edge (12), an u~per edge (14), and two curved lateral edge~ (16). In~d~litinn" the reflector bac~ panel is t~ nsioned and cu"~u~,d so as to provide
5 ~ n~l or Co~r~ >n~l ~bility to the overbing reflector. Su~table ~;r~
~ of the re~lector b~r~ panel ~clude formed ~ "i"",~, or molded Col~ ~;, such as
W l~_~t~lt ,~;~ol-,ed Lb~ s.
The flexible rellector (20) can assume a concave and cylin-l-n~ny arcuate
o c~.~r~ ;nn of ~ to 180 degrees. Yet, the le~,tol can be fle~ble enough to lie flat
when ulLs~polled. If l~l~ably, 1~ch~d to the reflector b~l ;n~ panel by
con~ r~ means, men 1~e ~ e~,t~ 9 a shape com~ t~ y to
the reflector b~t i~-~ paneL The le~c~.lor has a lower edge (22), an upper edge (Z3),
2md cuIved lateral edges (Z4). The ~kyw~u.l surface (26) of the reflector i~ ~e concave
l5 ~ c-e. Such a panel can be c~ ..; c~ of lld~ t, ultraviolct st~ili7P~ acIylic,
about 1.5 mm thick, and having powdered ~1-.",;,.--~ t. ,~ d onto the lower surface
(28) so a~ to create a reflectivity of at least 75~~, preferabb~ over 9~%. FIGURE 1
d~ the re~lector in an ex~loded view, the ~ su~ ded ab(Jve ~e backing
panel.
A structural ~u~ oll means, in this case a space truss (30), is di~poscd beneaththe reflector b~ panel and is co~ ed thereto, sen/ing as the structural support
means. The space t~uss is d;..,t ~ oned and cn-.1;~ ,d to support the weight of at
least the r~ tnr, the reflector b~ .~ panel, a reflected solar ener~y collector (50)
2s and a collector support means. A number of ~ e structural c~ alions can
be designed by those of oldil~y skill in the art.
A cnllector support means spans across and above the reflector. As shown ~n
FIGURE 1, the collector support means Cf.~ s two arches (42), a bearing means
30 (44) on each arch, a drive sha~ member (46) connected to the bearing means so as to
compl~c a IOt~t;l~ means, and two lower support ~ ,lbc s (48). The collector
5~
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support means is ~1; ..~ n - )nfd and el3..1~g.~d so to s.l~l,oll the eolleetor, and thus,
t~:~1iVe des~s are known to those of or~ skill m the art.
The reflected solar energy enl1eet~r (50) extends lateral~y aeross the re~eetor
s from eurved lateral edge (24) to eurved lateral edge (24). With the e~ t~ ;~ ny
areuate r~ne~ b~t il~ panels shown, one eould use a nu~n~er of known eoneetor
c~...r;~,..,~l;on~, but a more plefi,.l~,d eoneetor would use the eo~ d parabolic
shape as t1i~r~lose(l in U.S. ~,274,974 to Winston~ Thus, the collector L~ ed
and col~ulcd to reeeive refl~cte~1 solar energy mto an interior eonduit Illruugh whieh
0 a fluid can ~ow. The co~ .. ~ eonn~cb~ ;l to the arches (42) by the lower support
nc~ (48), whieh in tum, are c~ n~r- ~cl to the d~ive xha~ n~ 46), which in
tum, is eonneeted to the bearing means (44) d;~osed on eaeh arch ~II; r~n~ t points
(41) for the arches in the collector ~ l mearls are located a~ ~t to ~e upper
edge of the reflector. ~Alt~ *vely~ the arches could have been conn~cterl directly to
IS the :~LIu~lulal mean~s, such as a ~space tru~s or a ~u~J~ollillg surface that ~ d~ -l; s ~e
tuldl means.
~ the pl~f~ ,d emho&ent for cylint1ri~11y arcuate reflector bacl~r~, paneLs,
thc bearing means and drive shaft ~l~cn~kel are located at the center of curvature for the
20 reflector. I~e lower support ~ hel~ (48) are fii.~.cl~Fi~n~<l such that the solar energy
collector i~s located d~wl.~dr~ from ~e center of curvature by a .1;~ f~e L plu~, or
rninus 5% accor~ g to the formula: L = (R * 1.1)/2; where R equals the radius of the
curvature of the reflector. The above d~ -.I of ct~7 ..~ ..l~ allows the collector to
move arcuately within a pre~lc~ ~ ...;..cd focal zone for collectmg the reflected solar
25 energy from the reflector.
A means for positioning the collcctor, not shown, is connected to the dnve
shaft member (46). The po~iti~)nin~ means can comprise any of a n~ll~ of
conven~onal mcans in~ in~ a hydraulic motor driven by a hydraulic pump and
30 control means, an cl~ motor, or a mech~ni~l chainlgear or cable/pulley means.In any of these forms, the ~n~itionin~ means keeps the collector m an optimal position
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for col~ .g ~ ,t,,d solar energ;y w~in the focal c~ ction zone ~1UUU~1IUUI a
defined solar cycle. (I~,f~Lat)ly~ lthe defined solar cycle is the diurnal solar cycle.)
Thus, a mi,lopl~3cessol can be part of ~e po~iti~ means, c~ 1;"~, periodically
the optimal refl~cted solar energy ~th~in~ ~n~ n according to an ~Ig~nthm that
s takes into acco~lt the 1~titllde, ~e time of yeâr, and the time of d2~y, such z-l~,. ;~1....
being known to those of ~ skill in the art.
Finally, a co~v~ntion~l fh~id llal~Oll ~ystern, not shown, co..~ ~e condl~it
of ~e c~ ct r to a thermal energy use means or an energy storage means. The fluid
10 lla~ l means Cu~u]dt~,~ ~e solar ener~y-heated fh~id ~rou~h ~e c~?n-l-lit Su;table
ener~ al~r~. fluids are known to those of sk~l in the art~ inr~ in~ distilled water~
but more plef~,~al~ly for high tclLl~J~a~ al~r1ir~;on, include s~icone heat tla ~r~,~
fh~id (HIF), organic ~n~etic HTF, or ii~hi~it~,d ~Iycol HTF which can be used in a
..~ e range of from -lOOolF to 350(~F.
1~
All u~1i~ or ~ .rd patent ap~ fd herein are hereby
incol~ulated by lcrcl~,nce ~ereto.
~ Jiner emDo~ o~ me presenl inveniion are noi presenled nere wr~icn are
20 obvious to those of or~l;l~y skill in the art, now or dunng the term of any patent
issuing from ~is patent ~ ;r,~1 ;on, and thus, are wi~in the SpiIit and scope of the
present invention.
SW~3SrmSrE StlEET (RULE 2~)
